cache now implements models.Datastore by just embedding one and then changing
GetApp and GetRoute to have the cache inside. this makes it really flexible
for things like testing, so now the agent doesn't automagically do caching,
now it must be passed a datastore that was wrapped with a cache datastore.
the datastore in the server can remain separate and not use the cache still,
and then now the agent when running fn 'for real' is configured with the cache
baked in. this seems a lot cleaner than what we had and gets the cache out of
the way and it's easier to swap in / out / extend.
this adds `FN_` in front of env vars that we are injecting into calls, for
namespacing reasons. this will break code relying on the current variables but
if we want to do this, the chance is now really. alternatively, we could
maintain both the old and new for a short period of time to ease the
adjustment (speak now...). updated the docs, as well.
this also adds tests for the notoriously finicky configuration of the env vars
and headers when setting up a call. this won't test the container / request
for the call is actually receiving them, but it's a decent start and will yell
loudly enough upon formatting breakage.
added back FXLB_WAIT to a couple places so the lb can ride again
one thing for feedback:
headers are a bit confusing at the moment (not from this change, but that
behavior is kept here for now), we've a chance to fix them. currently, headers
in the request __are not__ prefixed with `FN_HEADER_`, i.e. 'hot'+sync containers
will receive `Content-Length` in the http request headers, yet a 'cold'
container from the same request would receive `FN_HEADER_Content-Length` in
its environment. This is additionally confusing because if this function were
hot+async, it would receive `FN_HEADER_Content-Length` in the headers, where
just changing it to sync goes back to `Content-Length`. If that was confusing,
then point made ;)
I propose to remove the `FN_HEADER_` prefix for request headers in the
environment, so that the request headers and env will match, as request
headers already are of this format (not prefixed). please lmk thoughts here
Would be fine with going back to the 'plain' vars too, then this patch will
mostly just be adding tests and changing `FN_FORMAT` to `FORMAT`. obviously,
from the examples, it's a bit ingrained now. anyway, entirely up to y'all.
* fix docker build
this is trivially incorrect since glide doesn't actually provide reproducible
builds. the idea is to build with the deps that we have checked into git, so
that we actually know what code is executing so that we might debug it...
all for multi stage build instead of what we had, but adding the glide step is
wrong. i added a loud warning so as to discourage this behavior in the future.
* hang the runner, agent=new sheriff
tl;dr agent is now runner, with a hopefully saner api
the general idea is get rid of all the various 'task' structs now, change our
terminology to only be 'calls' now, push a lot of the http construction of a
call into the agent, allow calls to mutate their state around their execution
easily and to simplify the number of code paths, channels and context timeouts
in something [hopefully] easy to understand.
this introduces the idea of 'slots' which are either hot or cold and are
separate from reserving memory (memory is denominated in 'tokens' now).
a 'slot' is essentially a container that is ready for execution of a call, be
it hot or cold (it just means different things based on hotness). taking a
look into Submit should make these relatively easy to grok.
sorry, things were pretty broken especially wrt timings. I tried to keep good
notes (maybe too good), to highlight stuff so that we don't make the same
mistakes again (history repeating itself blah blah quote). even now, there is
lots of work to do :)
I encourage just reading the agent.go code, Submit is really simple and
there's a description of how the whole thing works at the head of the file
(after TODOs). call.go contains code for constructing calls, as well as Start
/ End (small atm). I did some amount of code massaging to try to make things
simple / straightforward / fit reasonable mental model, but as always am open
to critique (the more negative the better) as I'm just one guy and wth do i
know...
-----------------------------------------------------------------------------
below enumerates a number of changes as briefly as possible (heh..):
models.Call all the things
removes models.Task as models.Call is now what it previously was.
models.FnCall is now rid of in favor of models.Call, despite the datastore
only storing a few fields of it [for now]. we should probably store entire
calls in the db, since app & route configurations can change at any given
moment, it would be nice to see the parameters of each call (costs db space,
obviously).
this removes the endpoints for getting & deleting messages, we were just
looping back to localhost to call the MQ (wtf? this was for iron integration i
think) and just calls the MQ.
changes the name of the FnLog to LogStore, confusing cause there's also a
`FuncLogger` which uses the Logstore (punting). removes other `Fn` prefixed
structs (redundant naming convention).
removes some unused and/or weird structs (IDStatus, CompleteTime)
updates the swagger
makes the db methods consistent to use 'Call' nomenclature.
remove runner nuisances:
* push down registry stuff to docker driver
* remove Environment / Stats stuff of yore
* remove unused writers (now in FuncLogger)
* remove 2 of the task types, old hot stuff, runner, etc
fixes ram available calculation on startup to not always be 300GB (helps a lot
on a laptop!)
format for DOCKER_AUTH env now is not a list but a map (there are no docs,
would prefer to get rid of this altogether anyway). the ~/.docker/cfg expected
format is unchanged.
removes arbitrary task queue, if a machine is out of ram we can probably just
time out without queueing... (can open separate discussion) in any case the
old one didn't really account well for hot tasks, it just lined everyone up in
the task queue if there wasn't a place to run hot and then timed them out
[even if a slot became free].
removes HEADER_ prefixing on any headers in the request to a invoke a call.
(this was inconsistent with cli for test anyway)
removes TASK_ID header sent in to hot only (this is a dupe of FN_CALL_ID,
which has not been removed)
now user functions can reply directly to the client. this means that for
cold containers if they write to stdout it will send a 200 + headers. for
hot containers, the user can reply directly to the client from the container,
i.e. with its preferred status code / headers (vs. always getting a 200).
the dispatch itself is a little http specific atm, i think we can add an
interchange format but the current version is easily extended to add json for
now, separate discussion. this eliminates a lot of the request/response
rewriting and buffering we were doing (yey). now Dispatch ONLY does input and
output, vs. managing the call timeout and having access to a call's fields.
cache is pushed down into agent now instead of in the front end, would like to
push it down to the datastore actually but it's here for now anyway. cache
delete functions removed (b/c fn is distributed anyway?). added app caching,
should help with latency.
in general, a lot of server/runner.go got pushed down into the agent. i think
it will be useful in testing to be able to construct calls without having to
invoke http handlers + async also needs to construct calls without a handler.
safe shutdown actually works now for everything (leaked / didn't wait on
certain things before)
now we're waiting for hot slots to open up while we're attempting to get ram
to launch a container if we didn't find any hot slots to run the call in
immediately. we can change this policy really easily now (no more channel
jungle; still some channels). also looking for somewhere else to go while the
container is launching now. slots now get sent _out_ of a container, vs.
a container receiving calls, which makes this kind of policy easier to
implement. this fixes a number of bugs around things like trying to execute
calls against containers that have not and may never start and trying to
launch a bazillion containers when there are no free containers. the driver api
underwent some changes to make this possible (relatively minimal, added Wait).
the easiest way to think about this is that allocating ram has moved 'up'
instead of just wrapping launching containers, so that we can select on a
channel trying to find ram.
not dispatching hot calls to containers that died anymore either...
the timeout is now started at the beginning of Submit, rather than Dispatch or
the container itself having to manage the call timeout, which was an
inaccurate way of doing things since finding a slot / allocating ram / pulling
image can all take a non-trivial (timeout amount, even!) amount of time. this
makes for much more reasonable response times from fn under load, there's
still a little TODO about handling cold+timeout container removal response
times but it's much improved.
if call.Start is called with < call.timeout/2 time left, then the call will
not be executed and return a timeout. we can discuss. this makes async play
_a lot_ nicer, specifically. for large timeouts / 2 makes less sense.
env is no longer getting upper cased (admittedly, this can look a little weird
now). our whole route.Config/app.Config/env/headers stuff probably deserves a
whole discussion...
sync output no longer has the call id in json if there's an error / timeout.
we could add this back to signify that it's _us_ writing these but this was
out of place. FN_CALL_ID is still shipped out to get the id for sync calls,
and async [server] output remains unchanged.
async logs are now an entire raw http request (so that a user can write a 400
or something from their hot async container)
async hot now 'just works'
cold sync calls can now reply to the client before container removal, which
shaves a lot of latency off of those (still eat start). still need to figure
out async removal if timeout or something.
-----------------------------------------------------------------------------
i've located a number of bugs that were generally inherited, and also added
a number of TODOs in the head of the agent.go file according to robustness we
probably need to add. this is at least at parity with the previous
implementation, to my knowledge (hopefully/likely a good bit ahead). I can
memorialize these to github quickly enough, not that anybody searches before
adding bugs anyway (sigh).
the big thing to work on next imo is async being a lot more robust,
specifically to survive fn server failures / network issues.
thanks for review (gulp)
* Renamed a bunch of images to use fnproject org.
* Multi-stage build for Docker.
* Added tmp vendor dirs to gitignore.
* Run docker-build at beginning of test.
API impact:
We need to drop default value for type because it brought this type of bugs.
Starting this patch users should specify route type through CLI or func.yml
Closes: #222
the mqs are storing a models.Task, which was not incorporating all the fields
that are in a task.Config. I would very much like to merge these two things,
but expect to do this in a future restructuring as both are used widely and
not cordoned off properly (Config has a channel, stdin, stdout, stderr -- and
isn't just a 'config', so to speak, as Task is).
Since a task.Config is what is used to actually run a container, the result of
the aforementioned deficiency was #193 where tasks are improperly configured
and ran (namely, memory wrong).
async tasks can still not be hot, they will be reverted to default format.
would also like to fix this (also part of restructuring). I actually started
doing this, hence the changes to those files (the surface area of the change
is small and discourages improper future use, so I've left what I've done).
this will:
closes#193closes#195closes#154
removes many unused fields in models.Task, since we have not implemented
retries. priority & delay are left, even though they are not used either,
the main goal of this is to resolve#193 and both these fields are strongly
plumbed into all the mqs, so punting on those two.
prior to this patch we were allowing 256MB for every function run, just
because that was the default for the docker driver and we were not using the
memory field on any given route configuration. this fixes that, now docker
containers will get the correct memory limit passed into the container from
the route. the default is still 128.
there is also an env var now, `MEMORY_MB` that is set on each function call,
see the linked issue below for rationale.
closes#186
ran the given function code from #186, and now i only see allocations up to
32MB before the function is killed. yay.
notes:
there is no max for memory. for open source fn i'm not sure we want to
cap it, really. in the services repo we probably should add a cap before prod.
since we don't know any given fn server's ram, we can't try to make sure the
setting on any given route is something that can even be run.
remove envconfig & bytefmt
this updates the glide.yaml file to remove the unused deps, but trying to
install fresh is broken atm so i couldn't remove from vendor/, going to fix
separately (next update we just won't get these). also changed the skip dir to
be the cli dir now that its name has changed (related to brokenness).
fix how ram slots were being allocated. integer division is significantly
slower than subtraction.
this changes the behavior of hot containers:
1) we are no longer populating a hot container with all of the env vars from the
first request to start up that hot container. this will only populate the
container with any vars that are defined on the app or route.
2) when env vars are changed on the route or app, we will now start up a new
hot container that contains those changes.
3) fixes a bug where we could have a collision if the image and path name
created one, e.g. `/yo/foo` & `oze/yo:latest` collides with `/yo/fo` and
`ooze/yo:latest` (if all other fields are held constant), since we're
name spacing with app name in theory it would happen to the same user (though
we were relying on a comma delimiter there, not great). now we use NULL bytes
which should be hard to get in through a json api ;) i added a sha1 to keep
the size of the (soon to be very large) map down, i don't expect collisions
but, well, it's a hash function.
a small note that we could add a few things to the hot container that will not
change on a request basis, such as `app_name`, `format` and `route` but it's a
bit pedantic. ultimately, it's confusing imo that we have a different set of
vars in the env and in the request itself for hot, which is unavoidable unless
we choose to omit setting env vars entirely, but it seems to be what the
people want (lmk, people, if otherwise).
Each time when MQ becomes unreachable HTTP GET /tasks returned HTTP 500
and code was not handling this case except expecting networking errors.
After that it tried to unmarshal empty response body that caused another sort of an error.
This patch triggers error based on http response code, explicitly checking if response code
is something unexpected (not HTTP 200 OK).
Response status code for /tasks for changed from 202 Accepted to 200 OK according to swagger doc.
the async stuff uses carlos supervisor thing but in the normal request path we
aren't catching any panics and returning a 500 to user (conn just gets
closed & server dies). should catch any mistakes we might make, or any one of
the 10000 libraries we're importing.
closes#150
we had this _almost_ right, in that we were trying, but we weren't masking the
error from the user response for any error we don't intend to show. this also
adds a stack trace from any internal server errors, so that we might be able
to track them down in the future (looking at you, 'context deadline
exceeded'). in addition, this adds a new `models.APIError` interface which all
of the errors in `models` now implement, and can be caught easily / added to
easily.
the front end now does no status rewriting based on api errors, now when we
get a non-nil error we can call `handleResponse(c, err)` with it and if it's a
proper error, return it to the user with the right status code, otherwise log
a stack trace and return `internal server error`. this cleans up a lot of the
front end code.
also rewrites start task ctx deadline exceeded as timeout. with iw we had
async tasks so we could start the clock later and it didn't matter, but now
with sync tasks time out sometimes just making docker calls, and we want the
task status to show up as timed out. we may want to just catch all this above
in addition to this, but this seems like the right thing to do.
remove squishing together errors. this was weird, now we return the first
error for the purposes of using the new err interface.
removed a lot of 5xx errors that really should have been 4xx errors. changed
some of the 400 errors to 409 errors, since they are from sending in
conflicting info and not a malformed request.
removed unused errors / useless errors (many were used for logging, and didn't
provide any context. now with stack traces we don't need context as much in
the logs).
